Means for cooling the blades of turbine rotors



Feb. 10, 1953 R. H. GODDARD 2,628,064

MEANS FOR COOLING THE BLADES OF TURBINE ROTORS Filed Jan. 2, 1948 Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE TMEAN S FOR. COOLING THE BLADES OF TURBINE ROTORS -Application January 2,1948, Serial No. 76

This invention relates to means for cooling the blades of a turbine rotor by the action of a cooling liquid, as water, delivered thereto.

This invention is particularly applicable to turbines which are driven by a blast of hot combustion gases, as in certain types of rocket apparatus.

It is the general object of this invention to provide improved means for liquid-cooling a set of turbine blades, and particularly when the blades are not enclosed at their peripheral edges.

In the preferred form, the cooling liquid is supplied at the inner portion of the rotor and is distributed to the blades by centrifugal force.

The invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claim.

Preferred forms of the invention are shown in the drawings, in which Fig. 1 is a side elevation of one form of the invention;

Fig. 2 is a sectional plan view of the rotor and certain associated parts;

Fig. 3 is a partial perspective view of the mechanism shown in Fig. 2;

Fig. 4 is a partial sectional side elevation of the rotor, taken along the line 44 in Fig. 2;

Fig. 5 is a partial sectional plan view showing a modified construction;

Fig. 6 is a partial sectional side elevation, taken along the line 6-6 in Fig. 5; and

Fig. 7 is a partial perspective view, looking in the general direction of the arrow 1 in Fig. 5.

Referring to Figs. 1 to 4, a turbine rotor R is shown which comprises an annular band III of V-shaped cross section which is mounted on a plurality of radiating partitions ll secured to a hub 12 fixed on a shaft l4. Side plates I 5 are secured to the outer edges of the ring l0 and are from the shaft [4.

Hollow turbine blades are mounted in spaced relation on the ring l0 and are slotted or perforated at their outer tips, as indicated at 2! in Fig. 4. These blades 20 are preferably doublecurved in plan, as clearly shown in Fig. 3, and are also backwardly curved in transverse section, as shown in Fig. 4.

The rotor R is so mounted that the tips of the l-Claim. (Cl. 253-39.15)

'40 provided with axial openings [6 spaced outward I blades 20 extend only into the outer portion 'of a blast of hot combustion gases issuing from a combustion chamber C through a nozzle N. The deflected gas portions are discharged laterally from the blades 20 against stationary guiding members by which their direction is reversed, so that they are redirected and finally discharged through passages 3| in a direction substantially parallel to the normal path of travel of the combustion gases.

For cooling the blades 20, a suitable cooling liquid, as water, is supplied under pressure through a fixed nozzle and through an annular opening [6 to the radiating spaces S which are defined by the side plates l5 and the partitions II. The cooling liquid flows outward through the spaces S by centrifugal force, and is discharged through the slots or openings 2| at the outer tips of the curved blades 2|]. The partitions II accelerate the centrifugal action.

The blades 20 are thus effectively cooled, and overheating is prevented.

In the construction shown in Figs. 5 to 7, a plurality of blades are mounted between discs '4l secured on a shaft 42. The blades 40 are curved in side elevation as shown in Fig. 5 to present a concave outer edge to the blast of combustion gases indicated by the circle G in Fig. 5. The blades are also curved in transverse section as shown in Fig. 6 and have lengthwise open channels 42a. The blades 40 are also provided with slots or openings 43 in their concave outer edges. These blades 40 are welded or otherwise secured to the plates 4| and are freely open through slots in the plates 4| to radiating jacket spaces S.

These jacket spaces S are formed between the discs 4| on the inside and casing members 44 on the outside. The members 44 are secured at their outer edges to the edges of the plates 4| and have axial openings 46 adjacent the shaft 42, through which openings water under pressure may be supplied from fixed nozzles 48.

Radiating partitions separate the jacket spaces S and hold the plates 4| and casing members 44 in definite spaced relation. The partitions 50 also provide more effective centrifugal action.

Water supplied through the nozzles 48 flows outward through the spaces S to the open ends 3 of the channels 42 in the blades 40. From these channels 42 the water or vapor will be ejected through the edge slots or openings 43.

With this construction also each blade is effectively cooled and overheating is avoided.

Having thus described the invention and the advantages thereof, it will be understood that the invention is not to be limited to the details herein disclosed, otherwise than as set forth in the claim, but what is claimed is:

In a turbine apparatus, a rotor having spaced hollow end discs enclosing jacket spaces, a plurality of hollow turbine blades mounted between said discs and secured thereto at their ends only and entirely supported thereby, said blades having their outer edges concave lengthwise and with no part of any blade extending radially beyond the peripheral outer edges of said discs, said blades having lengthwise passages open at each end of each blade through the inner sides of said discs to said jacket spaces and having discharge openings at their free peripheral concave outer edges, means to supply a cooling liquid to the jacket spaces in said hollow end discs, and a plurality of radiating partitions in the jacket space of each hollow end disc, which partitions sub- 4 divide said jacket spaces into radiating space portions through which said cooling liquid is fed 'by centrifugal force to the lengthwise passages in said hollow blades and through said blades to said edge-discharge openings.

ESTHER C. GODDARD. Executrzx of the Last Will and Testament of Robert H. Goddard, Deceased.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,255,924 Peaslee Feb. 12, 1918 2,390,506 Buehi Dec. 11, 1945 2,405,190 Darling Aug. 6, 1946 2,440,069 Bloomberg Apr. 20, 1948 FOREIGN PATENTS Number Country Date 11,014 Great Britain May 21, 1908 383,506 Germany Oct. 13, 1923 557,860 Germany Aug. 29, 1932 

